/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 */

package org.apache.jmeter.functions;

import java.io.Serializable;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;

import org.apache.jmeter.engine.util.CompoundVariable;
import org.apache.jmeter.samplers.SampleResult;
import org.apache.jmeter.samplers.Sampler;
import org.apache.jmeter.threads.JMeterContext;
import org.apache.jmeter.threads.JMeterContextService;
import org.apache.jmeter.threads.JMeterVariables;
import org.apache.jmeter.util.BeanShellInterpreter;
import org.apache.jmeter.util.JMeterUtils;
import org.apache.jorphan.logging.LoggingManager;
import org.apache.log.Logger;

/**
 * A function which understands BeanShell
 * 
 */
public class BeanShell extends AbstractFunction implements Serializable {

	private static final Logger log = LoggingManager.getLoggerForClass();

	private static final long serialVersionUID = 232L;
	
	private static final List desc = new LinkedList();

	private static final String KEY = "__BeanShell"; //$NON-NLS-1$

	public static final String INIT_FILE = "beanshell.function.init"; //$NON-NLS-1$

	static {
		desc.add(JMeterUtils.getResString("bsh_function_expression"));// $NON-NLS1$
		desc.add(JMeterUtils.getResString("function_name_paropt"));// $NON-NLS1$
	}

	private transient Object[] values;

	private transient BeanShellInterpreter bshInterpreter = null;

	public BeanShell() {
	}

	public Object clone() throws CloneNotSupportedException {
		return super.clone();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.jmeter.functions.Function#execute(SampleResult, Sampler)
	 */
	public synchronized String execute(SampleResult previousResult, Sampler currentSampler)
			throws InvalidVariableException {

		if (bshInterpreter == null) // did we find BeanShell?
		{
			throw new InvalidVariableException("BeanShell not found");
		}

		JMeterContext jmctx = JMeterContextService.getContext();
		JMeterVariables vars = jmctx.getVariables();

		String script = ((CompoundVariable) values[0]).execute();
		String varName = ""; //$NON-NLS-1$
		if (values.length > 1) {
			varName = ((CompoundVariable) values[1]).execute().trim();
		}

		String resultStr = ""; //$NON-NLS-1$

		log.debug("Script=" + script);

		try {

			// Pass in some variables
			if (currentSampler != null) {
				bshInterpreter.set("Sampler", currentSampler); //$NON-NLS-1$
			}

			if (previousResult != null) {
				bshInterpreter.set("SampleResult", previousResult); //$NON-NLS-1$
			}

			// Allow access to context and variables directly
			bshInterpreter.set("ctx", jmctx); //$NON-NLS-1$
			bshInterpreter.set("vars", vars); //$NON-NLS-1$
            bshInterpreter.set("props", JMeterUtils.getJMeterProperties()); //$NON-NLS-1$
			bshInterpreter.set("threadName", Thread.currentThread().getName()); //$NON-NLS-1$

			// Execute the script
			Object bshOut = bshInterpreter.eval(script);
			if (bshOut != null) {
				resultStr = bshOut.toString();
			}
			if (vars != null && varName.length() > 0) {// vars will be null on TestPlan
				vars.put(varName, resultStr);
			}
		} catch (Exception ex) // Mainly for bsh.EvalError
		{
			log.warn("Error running BSH script", ex);
		}

		log.debug("Output=" + resultStr);
		return resultStr;

	}

	/*
	 * Helper method for use by scripts
	 * 
	 */
	public void log_info(String s) {
		log.info(s);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.jmeter.functions.Function#setParameters(Collection)
	 */
	public synchronized void setParameters(Collection parameters) throws InvalidVariableException {

		checkParameterCount(parameters, 1, 2);

		values = parameters.toArray();

		try {
			bshInterpreter = new BeanShellInterpreter(JMeterUtils.getProperty(INIT_FILE), log);
		} catch (ClassNotFoundException e) {
			throw new InvalidVariableException("BeanShell not found");
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.jmeter.functions.Function#getReferenceKey()
	 */
	public String getReferenceKey() {
		return KEY;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.jmeter.functions.Function#getArgumentDesc()
	 */
	public List getArgumentDesc() {
		return desc;
	}

}
